Torque converters are positioned between the engine and transmission case of motorized vehicles. They play an important role by controlling on/off power from the engine to the rest of the drive train. In addition, they provide torque multiplication, dampen engine vibration and assure smooth start-ups and speed changes.
A typical torque converter assembly comprises as principal components, an impeller or pump, a turbine and a stator positioned between the turbine and pump. The turbine and pump are seated in opposing shells and rotate therewith. The torque converter pump is connected to the engine, and as the pump rotates energy is transmitted to the turbine by forcing fluid against turbine blades causing their rotation. The turbine, which is connected to the transmission, transmits torque to vehicle wheels. The torque converter pump also turns the transmission oil pump. The stator positioned between the turbine and impeller operates to redirect the flow of fluid allowing the pump to rotate with less torque, so as to provide torque multiplication.
Heretofore, when larger torque capacities were required, the usual practice was to increase the size of the torque converter. This however, has resulted in economic tradeoffs. Also contributing to overall higher costs has been the industry practice of manufacturing core assemblies for torque converters as multiple separate components requiring additional manufacturing steps.
While the foregoing practices have been effective in meeting needs for torque converters with greater torque capacities, there still remains an unfulfilled need for a solution to the problem of increasing torque capacity and overall values of torque converter performance, but with fewer significant economic trade-offs.